(Xi Xian) by a validated high-performance thin-layer chromatographic method. J. Planar Chromatogr. 30, 516-520 (2017). HPTLC of chlorogenic acid (1) and caffeic acid (2) in the leaves of Siegesbeckia orientalis on silica gel with toluene ‒ ethyl acetate ‒ formic acid ‒ methanol 30:30:8:3. Quantitative determination by absorbance measurement at 366 nm. The hRF values for (1) and (2) were 19 and 83, respectively. Linearity was between 200 and 600 ng for (1) and (2). LOD and LOQ were 20 and 40 ng/zone for (1) and 59 and 120 ng/zone for (2), respectively. The intermediate/interday/intra-day precisions were below 3 % (n=3). Recovery was 99.0 %.

CBS 118, 9-12 (2017). Comparison of TLC and HPTLC methods for (1) an aqueous-ethanolic extract of kidney vetch, (2) suppositories containing caraway extract, aqueously fermented root extracts of (3) barberry and (4) Solomon’s seal, and standards quinine hydrochloride, hyperoside, caffeic acid, rutin, fructose, caffeic acid, and noscapine hydrochloride. HPTLC on silica gel for (1) with chloroform – methanol – water 14:6:1, (2) with ethyl acetate – anhydrous formic acid – water 21:2:2, (3) with ethyl acetate – anhydrous formic acid – water 8:1:1 and (4) with chloroform – methanol – water 25:21:4. Detection by spraying with a (1) solution of 20 % antimony(III) chloride in chloroform and heating at 105 °C for 30 min, (2) 1 % methanolic solution of diphenylborinic acid 2-aminoethyl ester (natural products reagent), followed by a 5 % methanolic polyethylene glycol (macrogol) 400 solution and detection at UV 366 nm after 30 min, (3) bismuthate reagent (mixture of 0.85 g alkaline bismuth nitrate, 40 mL water, 10 mL acetic acid, and 20 mL potassium iodide solution (400 g/L), glacial acetic acid and water, 1:2:10), and (4) 1:1 mixture of 5 % sulfuric acid in ethanol and 2 % vanillin in ethanol and heating for 15 min at 105 °C. Compared to TLC, by HPTLC developing times were decreased, the separation power was higher and zones were sharper.

J. Planar Chromatogr. 31, 129-134 (2018). HPTLC of hydroxysafflor yellow A in safflower on silica gel with 3.6 % hydrochloric acid – methanol – ethyl acetate 7:3:1. Quantitative determination by absorbance measurement at 399 nm. The hRf value for hydroxysafflor yellow A was 60. Linearity (starting from LOD) was in the range of 62-793 ng/zone with r=0.9991. The intermediate precision was below 3 % (n=6). The LOD and LOQ were 59 and 169 ng/zone, respectively. Recovery was between 96 and 102 %.

J. Chromatogr. Sci. 55 (5), 571-577 (2017). Proposal of a rapid, easy and efficient method for calcium oxalate crystal inhibition in the agar gel system analogous to antimicrobial well diffusion assay, and TLC-agar-overlay bioautography (note that the term "direct bioautography" is wrongly used in the title) to detect the antilithiatic metabolites and to localize the active metabolites in Phyllanthus niruri, an Ayurvedic plant. The agar well diffusion method showed 50 % inhibitory concentration (IC50) value at 229 and 494 mg/mL for tri-sodium citrate and Phyllanthus niruri extract, respectively, with the lowest concentration showing visible crystal inhibition (minimum inhibitory concentration, MIC) of 20 mg/mL in both samples. With this method the successful screening, detection and confirmation of calcium oxalate crystal inhibitory metabolites from P. niruri was possible. Detection of tuberonic acid in the bioactive fraction of P. niruri by HPLC-HRMS.

and their herbal formulations. J. Planar Chromatogr. 31, 451-459 (2018). HPTLC of berberine chloride (1) and galangin (2) in Tinospora cordifolia M._x000D_ and Alpinia galanga on silica gel with toluene ‒ ethyl acetate ‒ formic acid 3:6:1. Quantitative determination by absorbance measurement at 267 nm. The hRF values for (1) and (2) were 17 and 82. Linearity was between 200 and 1200 ng/zone. LOD and LOQ were 28 and 86 ng/zone for (1) and 2 and 5 ng/zone for (2), respectively. The intermediate precision was <2 % (n=3). Recovery was between 97.5 and 102.6 % for (1) and (2).

J. Soil Sci. Plant Nutr. 18, 881-892 (2018). HPTLC of vasicine in Adhatoda zeylanica on silica gel with toluene – methanol – dioxane – ammonia 2:2:5:1. Qualitative identification under UV light at 343 nm. The hRF value for vasicine was 83.

Phytochemistry 25, 2135-2154 (1986). TLC investigation of 255 plant extracts for flavonoids and other phenolics on silica with toluene - pyridine - formic acid 100:20:7 or toluene - ethyl formate - formic acid 5:4:1, on polyamide with toluene - MEK - methanol 4:3:3 or on microcrystalline polyamide with nitromethane - methanol 4:3. Detection by UV. Systematic TLC study of plant flavonoids.

Helv. Chim. Acta 72, 668-674 (1989). TLC of saponins with molluscicidal activity on silica with ethyl acetate - methanol - water 17:2:1 and HPTLC on RP-8 with methanol - water 7:3. Detection with Godin reagent. TLC of saponin hydrolysate on silica with ethyl acetate - methanol - water - acetic acid 65:15:15:20 and on cellulose with ethyl acetate - pyridine - acetic acid - water 5:5:1:3. Detection of sugar by spraying with p-anisidine phthalate and of glucosamines with ninhydrin. Also HPLC and medium pressure liquid chromatography.